Bacteria are crawling all over things you don't even think about

Here are average total bacteria counts, per square inch, for a dozen common germ-infested items we encounter in our daily lives, according to Gerba, who has tested hundreds of surfaces. Check out these photos and click here for the related article.

Alexia Elejalde-Ruiz, Tribune Newspapers

Given how often they're on the floor, occasionally inside a public restroom, it should come as no surprise that a third of women's purses crawl with E. coli.

And given how many grubby hands and baby bottoms touch grocery store shopping carts, we shouldn't flinch at the fact that, on average, they carry 115 times more bacteria than a toilet seat.

It's a dirty world we're living in, and often our germiest encounters are not where we expect them. Not all germs are harmful, and healthy bodies can resist many illnesses. But the more people are exposed, the greater their chance of becoming infected with or transmitting a dangerous bug, from respiratory viruses to a host of foodborne bacteria. The Centers for Disease Control and Prevention estimates that each year 48 million Americans, or 1 in 6 people, get sick, 128,000 are hospitalized, and 3,000 die of foodborne diseases.

"You're always gambling with germs," said Dr. Charles Gerba, professor in the department of soil, water and environmental science at the University of Arizona. "The thing is to make the odds in your favor."

That means reducing exposure to germs, a feat best accomplished with regular hand-washing, using hand sanitizer and keeping your paws off your face, Gerba said.

It also means cleaning those grimy items you rarely think to clean, like remote controls and cellphones.

How often to scrub down depends on several factors. If you have kids or pets, if you are immunocompromised or someone in your household is sick, you may need to clean more thoroughly and frequently, said Donna Duberg, assistant professor of clinical lab science at Saint Louis University in St. Louis.

Need motivation? Here are average total bacteria counts, per square inch, for a dozen common germ-infested items we encounter in our daily lives, according to Gerba, who has tested hundreds of surfaces.